1. Field of the Invention
The present invention is applied to small gas engines for general-purpose use; in the main chamber that is demarcated by the engine main components such as the cylinder head, lean-burn combustion is performed; namely, the lean air-fuel mixture that is pre-mixed in an air-fuel (main fuel gas) mixer is burnt; the present invention relates to a fitting arrangement regarding a zero-governor that can suitably establish or regulate the pressure of the fuel gas supplied to the air-fuel mixer.
2. Background of the Invention
The patent reference (JP2001-73794) discloses a gas engine generator unit that is accommodated in a housing, as an example of farm working machinery; as shown in FIGS. 3 and 4 of this application in response to FIGS. 3 and 8 of the patent reference, the many components of a gasoline engine generator are used for the gas engine generator A; namely, the gas engine generator unit makes use of the components such as an engine unit U, a rigid frame F, an exhaust muffler 05 and an air cleaner Ac (not shown), as far as possible.
In the gas engine generator of the patent reference, the very upper half of a fuel tank provided in the gasoline engine generator is diverted to an upper cover Ca as a roof body of the gas engine; in the upper half space of the fuel tank, some components such as a zero-governor (a fuel gas pressure regulator) Z are provided; in addition, on the filler opening (the gasoline supply opening) of the fuel tank, an appropriate cap 020 instead of the filler cap is fitted.
In other words, in the gas engine disclosed by the patent reference, the upper half part of the fuel tank that is used in the gasoline engine generator is converted into a cover of the gas engine; and, the cap 020 is fitted on the cover.
In the patent reference (JP2001-73794) as described above, the upper half of a fuel tank provided in the gasoline engine generator is diverted to the upper cover Ca as a roof body of the gas engine; the zero-governor Z is arranged in the upper half of the fuel tank; in addition, on the filler opening of the fuel tank, the appropriate cap 020 instead of the filler cap is fitted.
However, the patent reference does not disclose effective utilization of the lower half of the fuel tank; namely, the lower half, just as it is, is not used in the gas engine generator, although the upper half is effectively utilized.
To be more specific, according to the patent reference, the upper half of the fuel tank for the gasoline engine is used as a cover provided with a capping function; the gas engine components such as the zero-governor Z is skillfully covered with the upper half of the fuel tank. According to the approach of the patent reference, however, the lower half part of the fuel tank for the gasoline engine is not directly (“directly” hereby means “just as it is”) utilized for the arrangements of the zero-governor and the fuel gas supply inlet-pipe; only the upper half of the fuel tank is utilized for such arrangements; thus, a lower cover Cb and a stay S are provided in the configuration (structure) according to the patent reference, so as to fit the zero-governor and the fuel gas supply inlet-pipe.